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—Paul Siegferth Jr., Akron, OH
This article appeared in our October 2008 issue.
Many indoor machines offer some kind of complicated algorithm to let users know the number of “miles” they have completed. However, not accounting for all the outdoor variables (wind, hills, impact, arm power, etc.) makes those numbers significantly inaccurate. So what’s a mile-counting maniac to do? There are two schools of thought: One, go by intensity/heart rate to equate your elliptical time to trail miles. For example, if your indoor workout feels “hard” (with a heart rate corresponding to what you would hit on the trail, if you use a monitor), divide your workout time by the number of minutes per mile you average on a “hard” trail run, and add that number of miles to your log.
Says Dick Brown, Ph.D., author of Fitness Running (Human Kinetics, 2003) and coach of 13 world-champion or Olympic athletes, if you do count miles for non-impact activities (such as elliptical training, biking, cross-country skiing and water running), “Remember you’re not getting the same pounding as on the trail, so your perceived effort might be exaggerated.” To be more accurate, consider exercising 10 percent longer than you would for an equivalent-mileage running workout. For example, if you normally cover six miles in 50 minutes, ride your bike for 55 minutes to count the workout as six miles of running.
Brown advocates an even simpler method for his athletes—do your workouts based on time and forget about miles. That includes interval-type workouts: For example, if you normally take about two minutes to run a quarter mile during speed-training sessions, you can just go for two minutes fast over and over, be it on skis, in water or on the elliptical.